1. Field of the Invention
The present invention relates to an erroneous connection preventing stopping plug to be inserted into a terminal receiving chamber of a connector housing, in which no terminal has been stored yet, so as to prevent erroneous connection with a mate terminal.
2. Background
For example, in a wire harness 121, a relay box 111, or the like, two or more connectors 122A and 122B, or 112A and 112B, which are the same in kind, are provided adjacently to each other as shown in FIGS. 10 and 11, so that there is a case where a mate connector 123 or a relay 113 is not connected to a certain connector (herein, the connector 122B or 112B) under a condition of circuit design on the destination side. In the case where there is such a useless connector 112B or 112B, an erroneous connection preventing stopping plug (hereinafter abbreviated to "stopping plug") is inserted to a terminal insertion hole 125 in order to prevent the mate connector 123 or the relay 113 from being erroneously connected to the connector 122B or 112B.
As a conventional example of the stopping plug, there is such a stopping plug for water proof as disclosed in JP-U-3-74482. For the sake of preventing erroneous connection, in this case, such a stopping plug 80 as shown in FIG. 12 is inserted into a terminal insertion hole from the front surface side of a connector.
FIG. 12 is a perspective view of the stopping plug 80 for preventing erroneous connection, and FIG. 13 is a side sectional view illustrating the relation between the stopping plug 80 and a connector housing 91 of a connector 90.
Generally, the connector housing 91 has a terminal receiving chamber 94 in which a terminal can be inserted from the rear, and a lance (flexible lock arm) 92 for locking the inserted terminal is provided inside the terminal receiving chamber 94. In addition, a mate-terminal insertion hole 93 is provided in a front wall 95 of the terminal receiving chamber 94, and guide slopes 96a and 96a are formed so as to spread outward in the front upper and lower portions of the hole wall of the mate-terminal insertion hole 93. The upper and lower guide slopes 96a and 96a guide a male mate-terminal to the mate-terminal insertion hole 93 when the male mate-terminal is to be inserted.
The stopping plug 80 has a plate-like body portion 81 which is to be inserted to the mate-terminal insertion hole 93 of the connector housing 91, and a head portion 82 provided at the rear end in the insertion direction thereof. A detachment preventing projection 83 which is to hit on a rear surface 97 of the front wall 95 of the connector housing 91 when the body portion 81 is inserted into the mate-terminal insertion hole 93, to thereby prevent the stopping plug 80 from coming off (in the direction opposite to the direction of insertion) is provided on the upper surface of the body portion 81. In addition, abutment surfaces 85 which are to abut on the guide slopes 96a and 96a of the connector housing 91 so as to prevent the stopping plug 80 from being inserted more are provided on the front upper and lower portions of the head portion 82.
When the terminal insertion hole 93 is blocked by this stopping plug 80, the body portion 81 of the stopping plug 80 is pushed into the terminal insertion hole 93 as shown by the arrow in FIG. 13. Then, the transformation of the connector housing 91 or the stopping plug 80 makes the detachment preventing projection 83 pass the terminal insertion hole 93 and enter the terminal receiving chamber 94 as shown in FIG. 14. Then, the abutment surfaces 85 provided in the head portion 82 abut against the guide slopes 96a and 96a of the terminal insertion hole 93 of the connector housing 91 so that the plug 80 stops there. As for the detachment direction, the detachment preventing projection 83 of the stopping plug 80 hits on the rear surface of the front wall 95 of the terminal receiving chamber 94 so as to prevent the detachment of the stopping plug 80.
Therefore, even if a mate connector or relay is fitted to this connector 90 erroneously, a male terminal of the mate connector abuts on the stopping plug 80 so that the male terminal cannot be inserted. Accordingly, it is possible to prevent erroneous connection. At this time, it is not necessary to insert stopping plugs to all the terminal insertion holes of the connector, and it is possible to prevent erroneous connection if a stopping plug is inserted to one of the terminal insertion holes.
In the conventional stopping plug 80, the rear end abutment surfaces 85 and 85 abut on the guide slopes 96a and 96a of the terminal insertion hole 93 of the connector housing 91 so as to prevent the stopping plug from being inserted more as shown in FIG. 15. However, since the connector housing 91 and the stopping plug 80 are made of resin and are locked by making the slopes abut on each other, there is a fear that the stopping plug 80 sinks down inside the connector housing 91 so as to make connection with a mate-connector 90B erroneously if an excessively strong pushing force is added to the stopping plug 80 by a male terminal 99 of the mate connector 90B as shown by the arrow (a).
FIGS. 22A to 26 show another conventional example illustrating the relation between a stopping plug 1 and a connector housing 11.
In FIGS. 22A and 22B, in the stopping plug 1, projections 7 and 7 having slope surfaces 5 and 5 are formed on a body portion 3 on its opposite side surfaces so as to axially extend from one side end portions to intermediate portions, respectively. In addition, a cover portion (head portion) 9 is formed on the other side of the stopping plug 1.
On the other hand, in a terminal receiving chamber 13 of the connector housing 11 in which the stopping plug 1 is to be inserted, front walls 17 and 19 are provided in one-side opening 15 to project from the edge portion as shown in FIGS. 23A, 23B and 24. A mate terminal is to be inserted into the terminal receiving chamber 13 between these front walls 17 and 19. In addition, this terminal receiving chamber 13 is set so that the inner width L1 thereof is longer than the width L2 of the stopping plug 1, and that the height L3 of the opening portion is longer than the thickness L4 of the stopping plug 1 as shown in FIGS. 22A, 22B, 23A and 23B. A flexible lock arm 21 is provided in this terminal receiving chamber 13 so as to project from the inner wall of the latter. This lock arm 21 is engageable with a terminal received in the terminal receiving chamber 13 thereby prevent the terminal from coming-off.
FIGS. 25A, 25B and 26 show the end surface of another terminal receiving chamber 25 in which a terminal hitting preventing wall 23 is formed on the opening edge portion. In this terminal receiving chamber 25, the width L5 of its opening portion is set to be shorter than the width L2 of the stopping plug 1 (FIG. 22A). In addition, the height L6 of the opening portion of the terminal receiving chamber 25 is set to be longer than the thickness L4 of the stopping plug 1 (FIG. 22B).
The stopping plug 1 is inserted from the one-side opening 15 of the terminal receiving chamber 13 to the inside as shown in FIGS. 23A, 23B and 24 so as to be installed in the terminal receiving chamber 13 through engagement of the projection 7 with the terminal stopping wall 17 at the opening edge portion of the terminal receiving chamber 13. Consequently, it is possible to prevent such erroneous connection that a mate terminal is erroneously connected into the terminal receiving chamber in which no terminal has been received yet.
If the width of the stopping plug 1 is set to be substantially equal to the width of the terminal receiving chamber 13, however, when the stopping plug 1 is inserted into the terminal receiving chamber 13 in which no terminal has been received yet, the insertion force becomes so large that the workability of insertion gets much worse. If the width of the stopping plug 1 is therefore set to be shorter than the width of the terminal receiving chamber 13 for the sake of easy insertion, there is a problem that looseness arises to generate abnormal sound.
In addition, when the stopping plug 1 is inserted into the terminal receiving chamber 25, it is impossible to insert the stopping plug 1 because the terminal hitting preventing wall 23 reduces the width of the opening of the terminal receiving chamber 25. If the width of the stopping plug 1 is set to be short enough to be inserted into the terminal receiving chamber 25, looseness arises when the stopping plug 1 has been inserted in the terminal receiving chamber 13.